Research identifies ways ageing may impact ability to get good night’s sleep

An elderly man stands in Copacabana in Rio de Janeiro September 13, 2011.
Reuters/Ricardo Moraes

A new study has looked into the effects of ageing on one's sleeping patterns. The researchers have identified a way for age to impair the circadian clock among mammals, affecting the ability to reset itself when exposed to light.

Research led by a University of Kent neurophysiologist learned that ageing leads to a significant reduction in sensitivity to light in a specific part of the brain called the suprachiasmatic nucleus (SCN). Its function is to control circadian rhythms.

The new study, published in the journal Neurobiology of Aging, offers suggestions about why people tend to find it more difficult to fall and stay asleep as they age. University of Kent's Gurprit Lall, along with his colleagues, also found that a glutamate receptor or NMDA becomes less effective in resetting the body's circadian clock as part of the process of ageing. NMDA transmits light information.

The team concluded that the ageing SCN faces structural reorganisation of its light-receiving components, impacting its function in both setting and maintaining a stable circadian rhythm. The researchers believe that their findings can help address issues with the circadian clock in older people.

"By establishing the significant changes in NMDA receptor configuration through age and the impact on circadian synchronization, we have uncovered a novel therapeutic target for the potential treatment of circadian misalignment in aged individuals," they wrote.

University of California Berkeley's Center for Human Sleep Science director Matthew Walker, who has written a book about the science of sleep, cited a link between sleep deprivation and some health problems. These include cancer, diabetes, Alzheimer's disease and poor mental health.

A number of studies have shown the hazards of sleep issues. For instance, a 2017 study shows that the brain could cannibalise itself due to sleep deprivation. Poor sleep is also often linked with increased risk for Alzheimer's disease because it is thought to contribute to higher amyloid levels. The National Sleep Foundation in the US also said it is a common misconception that the need for sleep declines with age.

RAND Europe also published a study in 2016 that examines the human and economic cost of not having enough sleep. The researchers found that individuals who regularly sleep less than six hours every night at any point in time had an increased mortality risk of 13 percent. Sleeping for less than six hours every night also increases a person’s chance of dying at any point in time by 13 percent.